1. Field of the Invention:
This invention relates to removal of chylomicrons, prebeta lipoproteins, and beta lipoproteins from human serum or plasma to prepare a stable optically clear serum.
2. Description of the Prior Art:
The use of pooled human serum or plasma in the preparation of chemical standards and quality control reference material for the assay of human blood serum constituents is well known. This pooled human serum or plasma is commonly stored as a dry powder after freezing or lyophilization to be reconstituted at the time of use. However, when lyophilized human serum or plasma is reconstituted with aqueous media, the resulting solution possesses variable amounts of turbidity, even though the original serum or plasma was optically clear. This turbidity produced upon reconstitution of lyophilized serum interferes with the analytical measurement of serum constituents.
Several patents disclose precipitation techniques for removing proteins from serum or plasma. Sample patents teaching such techniques are U.S. Pat. No. 2,922,745 (1960) to Singher et al, U.S. Pat. No. 3,560,475 to Fekete et al, (1971), and U.S. Pat. No. 3,682,881 (1972) to Fekete et al. While these patents do in fact disclose protein precipitation methods, in general, the procedures prevent the use of the remaining serum as a standard for certain tests and do not lend themselves readily to large scale processing, others yield crude products by modern standards and in still others the overall yields are low.
A method for removal of lipoproteins from serum by specific precipitation is disclosed by Burstein, Scholnick, and Morfin in The Journal of Lipid Research, Volume 11 (1970), pages 583-595. This method, however, is directed towards obtaining lipoproteins in purified form and makes no mention of additional steps needed to be done to the serum for its use as a standard.